Resistance unit.



L. E. BARRINGER.

RESISTANCE UNIT. APPLICATION FILED JULY 14, 1910.

Patented May 14, 1912.

Inventor Lavv F8T1C EBarnnqer;

Witnesses:

A ttorn ey.

t ya certain new and useful Improvements in ,UNITED 1 STATES PATENT OFFICE.

LAWRENCE E. BABBINGER, OF SCHENECT ADY, NEW

YORK, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

nnsrsrmcn UNIT.

- Specification of Letters Patent.

Application filed July 1T4, 1910. SerialNo. 571,912.

To all 'wkomz't may concern:

Be it known that I, LAWRENCE E. BAR- RINGER, a citizen of the United States, re-

siding at Schenectady, county of Schenec- Sta'teof New York, .have invented Resistance Units, of which the following is V a specification.

This invention relates to the manufacture of resistance devices for electric circuits and has for its object the provision of 'an 1m proved device of this character which wil be simple and rugged in construction andat the same time thoroughly reliable and efiicient.

My invention relates more specifically to I resistance units of the type in e which a resistance conductor is mounted upon a'rigid insulating support so as to form a selfcontained unit for use either alone or.in connection with other units in various electrical applications.

One way in which resistance units have heretofore been made is by mounting the upon an insulating supresistance conductor port, such as porcelain, and cementlng 1t to the support in some manner, as for instance, by means of glaze or enamel. These insulating supports have commonly taken the form of porcelain tubes on the outside of which the resistance conductor is wound. The tube with the wire on it isthendipped in enamel and fired. One-of the great difiiculties which has been encountered in-units thus constructed is the liability of breakage. Porcelain,

suited for the purpose since it is both fireproof and water-proof, is nevertheless verybrittle and such and com letely destroy the unit.

Oneo the objects of myinvention, therefore, is to improve this type of unit by a tube if dropped will break rendering the same strong and rugged,-while 1 at the same time preserving the characteristic qualities ofthe material. In carrying out my invention I strengthen the insulating materialby cementing thereto a metallic element. This I do in the case of a porcelain tube by enameling or glazing a metallic tube to the inside of the porcelain tube. A resistance wire is then wound on the tube and coated with enamel and the whole fired so as to unite the parts together and form-a rigid structure.

In the accompanying drawing disclosing.

the form of a while being otherwise very wellmy invention embodied in concrete form,-

Igure'l is a view partly in'section of a porcelain tubewound with wire; Fig. 2 is a similar view of the metallic-tube coated with enamel; and Fig. 3 is asimilar view of.

10 represents- In order to simplify Patented May 14, 1912.

I have shown ductor and coat the same with enamel 14. p

The tube 12 coated with the enamel 13 is insertedwithin the porcelain tube and the assembled unit fired. The firing fuses the enamel between the iron and porcelain and thereby cements the tubes into a rigid structure and at the same time fuses the enamel on theresistance conductor, thereby cement ing the conductor to the porcelain and embedding it inthe material, which, is refractory and moisture proof. This makes theunit practically indestructible and even if the unit were roughly handledin such a way as to break the porcelain the unit would not be destroyed, since the parts would still adhere together and be ready for. service.

' It will be understood, of course, that while I have described my invention as-beinig formed in a definite manner. with spec1 0 materials, I do not limit my invention in these particulars, since various modifications thereof will suggest themselves to those skilled in the art without departing from the spirit of my invention, the scope of which is set forth in the annexed claims. at I claim as new and desire to secure by Letters Patent of theUnitedStates is: 1. A resistance unit comprising a tubular insulating support having a metallic member enameled to the inner surface thereof and a resistance conductor enameled to the outer surface.

.2. 'A resistance unit comprising a support of porcelain and metal enameled to- 5. The processof making resistance units which consists in winding a resistance conductor on an insulating tube, coating the same with enamel, then member with enamel inserting it within the insulating tube, and firing the whole to cement the parts together.

In witness whereof, I- have hereunto set my hand this 11th day of July, 1910.

LAWRENCE E. BARRINGER.

Witnesses:

BENJAMIN B. HULL,

Hum 0mm);

get-her and a-resistance conductor enameled' to the-porcelain. v

3.- A resistance unit com rising a support composed of a orcelain tu e having a metal tube enameled to the inner surface thereof and a resistance conductor enameled to the outer surface. 7

4. The process of making resistance units which consists in mounting a resistance conduct-or on an ins lating support, coating the same with enamel, enameling a metallic member to the support and firing to unite.

the parts.

coating a metallic 

